Disclosed herein, in various embodiments, are compositions and processes for making stable, high performing electronic features useful in various electronic devices.
Fabrication of electronic circuit elements using liquid deposition techniques may be beneficial as such techniques provide potentially low-cost alternatives to conventional mainstream amorphous silicon technologies for electronic applications such as thin film transistors (TFTs), light-emitting diodes (LEDs), RFID tags, photovoltaics, etc. However, the deposition and/or patterning of functional electrodes, pixel pads, and conductive traces, lines and tracks which meet the conductivity, processing, and cost requirements for practical applications have been a great challenge.
The metal, silver, is of particular interest as conductive elements for electronic devices because silver is much lower in cost than gold and it possesses much better environmental stability than copper. Silver nanoparticles have attracted extensive interest for making highly conductive features at low annealing temperatures. However, there are two major challenges associated with current silver nanoparticles. First, to allow their use on a wide range of flexible plastic substrates, a low processing temperature, ideally below 120° C., is preferred to maintain the dimensional stability of the flexible substrates. Second, it has been difficult to develop silver nanoparticles that have a processing temperature below 120° C. while still having sufficient shelf-life stability. Generally, annealed films or printed lines obtained from aged silver nanoparticle compositions suffer significant loss in conductivity. It would be desirable to develop compositions and processes that allow aged compositions to have the same high level of conductivity as freshly prepared compositions at low processing temperatures.